2.2 ecotec tuning - fueling issues, p0140 code

I have a customers vehicle in for tuning. 2.2 Ecotec swap into an older vehicle.
I'm not very familiar with the P11 ecu's as I don't ever do them.
They seem simple enough.

Here is my problem: I'm trying to get close to WOT and the ECU throws a P0171 code (Lean Bank 1).
It's not actually lean. i have verified this on my dyno with a wideband.

What I am seeing is the mV on the factory 02 sensor doing goofy stuff!!!

Past that, has anyone else ever came across issue's like this on a P11?
I've disabled all of the smog equipment and VATS due to it being a swap.
The ECU was modified prior to me receiving the headache. I've compared this vehicles file to a few different stock files (I couldn't fine any files with the exact same OS). It looks like typical stuff touched: PE, VATS, Spark, VE. Nothing major.

But this thing is doing some goofy stuff!

Any help would be appreciated. Thank you!

Attachment 75302
Attachment 75303
Attachment 75304
Attachment 75305
Attachment 75306